In 2012, YouTube made a change to its algorithm to prioritize watch time instead of view count, leading to a 20 percent drop in daily view count in one day. Prior to the change, the algorithm led to users clicking through several videos before finding what they were looking for. YouTube’s director of engineering for search and discovery Cristos Goodrow says: “We realized that if we made the viewer click that many times, it didn’t seem to be a good estimate of how much value they were deriving from YouTube. Instead, we realized that if they didn’t leave a video and continued watching, that seemed like a better estimate of the value they were getting.”